Device and method for manufacturing soft metal tube

ABSTRACT

Firstly, a heat transfer tube, in which grooves are formed on its inside surface in groove working step ( 1 ) and then its forming is applied in forming step ( 2 ), is softened in annealing step ( 3 ). Then, the tube is coiled in line in coiling in-line step ( 4 ). Here, while supplied in the length direction, the heat transfer tube is heated and cooled in the annealing step ( 3 ). Further, in the coiling in-line step ( 4 ), the heat transfer tube is coiled in line on a body of bobbin, so that works of installing the heat transfer tube to the bobbin can be simplified.

TECHNICAL FIELD

[0001] The present invention relates to a method and a device formanufacturing a soft metal tube in which a hardening work is applied inmanufacturing a heat transfer tube with its inside surface having agroove for a heat exchanger or the like. More specifically, the presentinvention relates to a measure to prevent contacted portions of themetal tube that is coiled in line from sticking together.

BACKGROUND ART

[0002] For example, a heat transfer tube with its inside surface havinga groove for a cross fin coil for an air conditioner shown in JapanesePatent Publication No. 61-32599 uses a soft copper plate as itsmaterial. As this soft copper plate, for example, a copper alloy platethat is defied by “O-material” of the alloy number “C1220” in “Chart 4Mechanical Property” in the JIS (the Japanese Industrial Standards) H3300 “Plate and Line of Cupper and Cupper Alloy” may be used.

[0003] A process of manufacturing a heat transfer tube using theabove-described soft cupper plate will be described referring to FIGS. 4and 5. Firstly, groove working by rolling is applied to a copper plateby groove working means (61) in groove working step (51). Then, informing step (52), it is formed in a tube shape by forming means (62) insuch a manner that the groove is located on an inside surface of thetube. The copper tube (B) formed in this way is coiled regularly and inline by coiling in-line means (63) in coiling in-line step (53), andthen it is installed to a bobbin for carrying out (C) in installmentstep (55) to be shipped subsequently.

[0004] Here, the copper plate is hardened to be H-material (as definedin the above-described Chart 4) by rolling in the groove working step(51). Accordingly, only this process would just provide a hardenedcopper tube (B). Specifically, Vickers Hardness HV(0.5) [÷HV(4.9 N)] ofthe copper plate increases from 60-68 before working to 100-130 afterworking, Further, in the case of the heat transfer tube, its elongationpercentage, one of important factors in forming the cross fin coil,decreases from 40% before working to 35% after working.

[0005] Accordingly, in a conventional process, the copper tube (B) isannealed and softened in annealing step (54) that follows the coilingin-line step (53).

[0006] Now, a process from the coiling in-line step (53) through theannealing step (54) to the installment step (55) will be described indetail referring to FIG. 6.

[0007] Firstly, in the coiling in-line step (53), as shown in FIG. 6(a),the copper tube (B) is coiled regularly and in line by a coiling machine(63 b), applying a bending tendency to the hardened copper tube (B) by abending roll (63 a). In this way, the copper tube (B) that is coiled inline can be provided as shown in FIG. 6(b).

[0008] Next, this copper tube (B) that is coiled in line, as shown inFIG. 6(c), is heated in an annealing furnace (64), a large anoxicfurnace, and then it is removed out of the annealing furnace (64) andcooled naturally, as shown in FIG. 6(d). In this way, the copper tube(B) that is coiled in line can be softened.

[0009] Then, as shown in FIG. 6(e), a body (C1) of the bobbin forcarrying out (C) is inserted in the center of the coils of the coppertube (B), and a pair of flanges (C2, C2) are attached to both ends ofthe body (C1), respectively. In this way, the copper tube (B) that iscoiled in line can be installed to the bobbin (C).

[0010] Here, the reason the copper tube (B) is not annealed after it hasbeen coiled in line to the bobbin (C) is to prevent the bobbin (C) frombeing heated. In this way, the soft cupper tube (B) with its insidesurface having a groove can be provided as shown in FIG. 6(f).

[0011] Problems to be Solved

[0012] Meanwhile, in the conventional manufacturing process describedabove, when the copper tube (B), which is coiled in line in the coilingin-line step (53), is heated in the annealing step (54), contactedportions of the copper tube (B) may stick together. Accordingly, thereis a defect that it may not be easy for the copper tube (B) coiled onthe bobbin (C) to be removed. Especially, a considerably high tensionneeds to be applied to the copper tube (B) when the copper tube (B) iscoiled in line in the coiling in-line step (53). Accordingly, there maybe some portions of the copper tube (B) where there exists a strongcontact stress. Those portions may stick together very easily.

[0013] In view of the above-mentioned conventional problem, it is amajor object of the present invention is to prevent contacted portionsof a soft metal tube from sticking together because of annealing appliedfor softening the metal tube, by applying an appropriate manufacturingmethod, when the soft metal tube, such as a heat transfer tube with itsinside surface having a groove, is manufactured in which a hardeningwork is applied to the metal tube and it is coiled in line for itsinstallment to an bobbin, resulting in an easy removal (un-coiling) ofthe metal tube from the bobbin.

DISCLOSURE OF THE INVENTION

[0014] In order to achieve the above object, the present inventionprovides a method and a device for manufacturing a soft metal tube inwhich the metal tube is coiled in line after being annealed, contrary toa conventional way in which the metal tube is annealed after beingcoiled in line, so that contacted portions of the metal tube can beprevented from sticking together.

[0015] Specifically, the first aspect of the invention, as shown in FIG.1, provides a method for manufacturing a soft metal tube, comprisingworking step (1) of working a soft metal plate with hardening of thesoft metal plate, forming step (2) of forming the metal plate worked inthe working step (1) into a metal tube (B), annealing step (3) to annealand soften the metal tube (B) that is hardened in the working step (1)and formed in the forming step (2), and coiling in-line step (4) ofcoiling the metal tube (B) softened in the annealing step (3) in line.

[0016] According to the first aspect of the invention, the soft metalplate is hardened by groove working in the working step (1) and thenformed into the metal tube (B) in the forming step (2). It means thatthis would just provide only a hardened metal tube. However, the abovemetal tube (B) is firstly softened in the annealing step (3) and thencoiled in line in the coiling in-line step (4). That is, in theannealing step (3), the metal tube (B) has not been coiled in line yet.Accordingly, a situation can be avoided where contacted portions of themetal tube (B) stick together by annealing and thereby it may not beeasy for the coiled tube to be removed.

[0017] Further, the second aspect of the invention provides the methodof the first aspect of the intention, wherein the working step (1)comprises rolling to harden the metal plate.

[0018] According to the second aspect of the invention, the metal plateis actually hardened by rolling in the working step (1), because ingeneral applying rolling to a soft metal plate hardens the metal plate.Therefore, the above-described function of the first aspect of theinvention can be achieved actually.

[0019] Further, the third aspect of the invention provides the method ofthe first aspect or the second aspect of the invention, wherein theannealing step (3) comprises step of annealing every portions of themetal tube (B) one by one and continuously while the metal tube (B) issupplied in the length direction, and the coiling in-line step (4)comprises step of coiling the metal tube (B) in line successively whilethe metal tube (B) is carried out from the annealing step (3).

[0020] According to the third aspect of the invention, in the annealingstep (3), every portions of the metal tube (B) is annealed one by oneand continuously while supplied in the length direction. Meanwhile, inthe coiling in-line step (4), the metal tube (B) is coiled in linesuccessively while carried out from the annealing step (3). Accordingly,a smaller annealing furnace can be adopted, compared with that used in aconventional way where each coil of the metal tube coiled in line isannealed one by one. Further, in the annealing step (3), the annealingof the metal tube (B) is applied in the length direction continuously,and therefore a lower cost can be achieved, compared with a conventionalway where applying of annealing is applied intermittently for each coilof the metal tube.

[0021] Further, the fourth aspect of invention provides the method ofany of the first aspect through the third aspect of the invention,wherein the metal tube (B) is carried out in a state where it is coiledin line on a bobbin for carrying out (C), and the metal tube (B) iscoiled in line on the bobbin for carrying out (C) in the coiling in-linestep (4).

[0022] According to the fourth aspect of the invention, the metal tube(B), for example like a heat transfer tube for a heat exchanger, iscarried out in a state where it is coiled in line on a bobbin forcarrying out (C), and the metal tube (B) is coiled in line on the bobbinfor carrying out (C) in the coiling in-line step (4) that is after theannealing step (3). That is, because the annealing step (3) is finishedat this point, a situation where the bobbin for carrying out (C) isheated can be avoided. Therefore, any work of installing the metal tubethat is coiled in line to the bobbin (C), which exists in a conventionalway, can be omitted.

[0023] Further, the fifth aspect of the invention provides the method ofthe fourth aspect of the invention, wherein the bobbin for carrying out(C) comprises a body (C1) on which the metal tube (B) is coiled and aflange (C2) which is attached to at least one end of the body (C1), andthe metal tube (B) is coiled in line on the body (C1) and then theflange (C2) is attached to the body (C1) with the metal tube (B) coiledin line thereon in the coiling in-line step (4).

[0024] According to the fifth aspect of the invention, in the coilingin-line step (4), the metal tube (B) is coiled in line on the body (C1)and then the flange (C2) is attached to the body (C1). Therefore, anywork of inserting the body (C1) into the center of the coils of themetal tube (B) coiled in line, which exists in a conventional way,should not be necessary, and so it can provide simple works in themanufacturing method.

[0025] Further, the sixth aspect of the invention provides the method ofany of the first aspect through the fifth aspect of the invention,wherein the metal tube (B) is a heat transfer tube with its insidesurface having plural lines of grooves for a heat exchanger and themetal plate is a copper plate, the forming step (1) comprises step offorming plural lines of grooves on one surface of the copper plate byrolling, and the forming step (2) comprises step of forming the copperplate into the heat transfer tube (B) for the heat exchanger in such amanner that the grooves are located on an inside surface of the tube.

[0026] According to the sixth aspect of the invention, plural lines ofgrooves are formed on one surface of the soft copper plate by rolling inthe working step (1), and the copper plate is formed in a tube shape insuch a manner that the grooves are located in an inside surface thereofin the forming step (2), and then the heat transfer tube with its insidesurface having a groove (B) is provided. Therefore, the heat transfertube with its inside surface having a groove (B) that should be easy tobe removed without sticking because of annealing can be provided.

[0027] Further, the seventh aspect of the invention provides amanufacturing device that is used for the above-described method formanufacturing a soft metal tube of the first aspect of the invention, asshown in FIG. 2, comprising, working means (11) for working a soft metalplate with hardening of the soft metal plate, forming means (12) forforming the metal plate worked in the working means (11) into a metaltube (B), annealing means (13) for annealing and softening the metaltube (B) that is hardened in the working means (11) and formed in theforming means (12), and coiling in-line means (14) for coiling the metaltube (B) softened in the annealing means (13) in line. According to thisdevice for manufacturing a soft metal tube, basically the same functionas the first aspect of the invention can be achieved.

[0028] Further, the eighth aspect of the invention provides the deviceof the seventh aspect of the invention, wherein the working means (11)rolls the metal plate accompanying hardening of this metal plate.According to the eighth aspect of the invention, basically the samefunction as the second aspect of the invention can be achieved.

[0029] Further, the ninth aspect of the invention provides the device ofthe seventh aspect or the eighth aspect of the invention, wherein theannealing means (13) comprises means for annealing every portions of themetal tube (B) one by one and continuously while the metal tube (B) issupplied in the length direction, and the coiling in-line means (14)comprises means for coiling the metal tube (B) in line successivelywhile the metal tube (B) is carried out from the annealing means (13).According to the ninth aspect of the invention, basically the samefunction as the third aspect of the invention can be achieved.

[0030] Further, the tenth aspect of the invention provides the device ofthe ninth aspect of the invention, wherein the annealing means (13)comprises a heating furnace (13 a), through which the metal tube (B) canpass in the length direction, and a cooling furnace (13 b) coupled tothe heating furnace (13 a) at its exit side, through which the metaltube (B) coming out from the heating furnace (13 a) can pass in thelength direction, and every portions of the metal tube (B) in the lengthdirection passing through are heated in the heating furnace (13 a) andthen cooled in the cooling furnace (13 b), one by one and continuously,respectively. According to the tenth aspect of the invention, thefunction of the ninth aspect of the invention can be achievedappropriately.

[0031] Further, the eleventh aspect of the invention provides the deviceof any of the seventh aspect through the tenth aspect of the invention,wherein the metal tube (B) is carried out in a state where it is coiledin line on a bobbin for carrying out (C), and the coiling in-line means(14) coils the metal tube (B) in line on the bobbin for carrying out(C).

[0032] According to the eleventh aspect of the invention, the metal tube(B) that is annealed by the annealing means (13) is coiled in on thebobbin for carrying out (C) by the coiling in-line means (14). Accordingto the eleventh aspect of the invention, basically the same function asthe fourth aspect of the invention can be achieved.

[0033] Further, the twelfth aspect provides the device of any of theseventh aspect through the eleventh aspect of the invention, wherein themetal tube (B) is a heat transfer tube with its inside surface havingplural lines of grooves for a heat exchanger and the metal plate is acopper plate, the working means (11) forms plural lines of grooves onone surface of the copper plate by rolling, and the forming means (12)forms the copper plate into the heat transfer tube (B) for the heatexchanger in such a manner that the grooves are located on an insidesurface of the tube. According to the twelfth aspect of the invention,basically the same function as the sixth aspect of the invention can beachieved.

[0034] Effects

[0035] As described above, according to the first aspect and the seventhaspect of the invention, the soft metal plate is worked with hardeningthereof and formed in a tube shape, and the metal tube (B) is coiled inline. Here, when the hardened metal tube (B) is softened by annealing,the metal tube is coiled in line after being annealed, contrary to aconventional way in which the metal tube is annealed after being coiledin line. Therefore, contacted portions of the metal tube (B) can beprevented from sticking together.

[0036] According to the second aspect and the eighth aspect of theinvention, the work with hardening is the rolling. Therefore, the effectof the first aspect and the seventh aspect of the invention can beachieved actually.

[0037] According to the third aspect and the eighth aspect of theinvention, the formed metal tube (B) is annealed continuously whilesupplied in its length direction, and thereby a smaller annealingfurnace can be adopted. Therefore, space saving of equipments and costreduction for installing and operating equipments can be achieved.

[0038] According to the fourth aspect and the ninth aspect of theinvention, the metal tube (B) is carried out in a state where it iscoiled in line on a bobbin for carrying out (C), and the metal tube (B)is coiled in line on the bobbin for carrying out (C) in the coilingin-line step (4). Therefore, it can reduce works for installing themetal tube (B) to the bobbin (C).

[0039] According to the fifth aspect of the invention, the metal tube(B) is coiled in line on the body of the bobbin (C), in which itsflanges are attached to the end of its body. Therefore, any work ofinserting the body into the center of the coils of the metal tube (B)coiled in line can be omitted. As a result, it can achieve the effect ofthe fourth aspect and the eleventh aspect of the invention actually.

[0040] According to the sixth aspect and the twelfth aspect of theinvention, the metal tube (B) is the heat transfer tube with its insidesurface having a groove for the heat exchanger, and this heat transfertube for the heat exchanger is made from the copper plate. Therefore,the heat transfer tube with its inside surface having a groove thatshould be easy to be removed from the bobbin for carrying out (C) can beprovided.

[0041] According to the tenth aspect of the invention, every portions ofthe metal tube (B) in its length direction are annealed one by one andcontinuously by the heating furnace (13 a) and the cooling furnace (13b), through which the tube can pass respectively. Therefore, it canachieve the effect of the third aspect and the ninth aspect of theinvention actually.

BRIEF DESCRIPTION OF DRAWINGS

[0042] In the accompanying drawings:

[0043]FIG. 1 is a block diagram showing a process of manufacturing aheat transfer tube in an embodiment of the present invention;

[0044]FIG. 2 is a block diagram showing an entire constitution of amanufacturing device;

[0045]FIG. 3 is a schematic illustration showing respective steps in amanufacturing process from annealing step to coiling in-line step;

[0046]FIG. 4 is a diagram equivalent to the FIG. 1, showing aconventional process of manufacturing a heat transfer tube;

[0047]FIG. 5 is a diagram equivalent to FIG. 2, showing an entireconstitution of a conventional manufacturing device; and

[0048]FIG. 6 is an illustration equivalent to FIG. 3, showing respectivesteps in a conventional manufacturing process from annealing stepthrough coiling in-line step to installment step.

BEST MODE FOR CARRYING OUT THE INVENTION

[0049] Hereinafter, a preferred embodiment of the present invention willbe described with reference to the accompanying drawings.

[0050]FIG. 2 shows schematically an entire constitution of amanufacturing device of a heat transfer tube in the embodiment of thepresent invention.

[0051] This device is used for manufacturing a heat exchanger from aribbon-shaped soft copper plate of about 0.5 mm in thickness and about30 mm in width (mentioned in Prior Art section). The manufacturingdevice is used for manufacturing a heat transfer tube (B) with itsinside surface having a groove, having a thickness of several mm (forexample, 7-8 mm).

[0052] The manufacturing device basically includes a groove workingmechanism (11) that forms plural lines of grooves by applying rolling tothe soft copper plate, a forming mechanism (12) that forms the copperplate worked by the groove working mechanism (11) into the heat transfertube (B), an annealing mechanism (13) that anneals and softens the heattransfer tube (B) which is hardened by the groove working mechanism (11)and formed by the forming mechanism (12), and a coiling in-linemechanism (14) that coils the beat transfer tube (B) softened by theannealing mechanism (13) regularly and in line.

[0053] When supplied to the manufacturing device, the copper plate issupplied in a state where it is coiled on a bobbin for carrying in. Onthe other hand, the beat transfer tube (B) formed by the manufacturingdevice is carried out in a state where it is coiled regularly and inline on a wooden bobbin for carrying out (C) having a cylindrical body(C1) and a pair of flanges (C2, C2) detachably attached to the both endsof the body (C1).

[0054] The bobbin for carrying out (C) has its size in which an outsidediameter of the body (C1) is approximately 600 mm, a distance betweenthe both flanges (C2, C2) is approximately 400 mm, and a diameter ofeach flange (C2) is approximately 1100 mm.

[0055] Specifically, the groove working mechanism (11) is coupled to anun-coiler that removes the coiled copper plate on the bobbin carried in,which is not illustrated. The groove working mechanism (11) isconstituted in such a manner that an emboss roll with a certain outerfigure is pressed against the copper plate removed by the un-coiler soas to form the groove described above.

[0056] The forming mechanism (12) is constituted in such a manner thatthe copper plate is formed in a tube shape by pressing the copper plateagainst a forming roll mold, both-side edges thereof in the widthdirection are attached to one another and welded together by a weldingmachine, and then it is narrowed down to a certain diameter, which innot illustrated. In this way, the heat transfer tube (B) is formed bythe forming mechanism (12).

[0057] The annealing mechanism (13) includes a high-frequency heatingfurnace (13 a), through which the heat transfer tube (B) can pass in thelength direction thereof, and a cooling furnace (13 b) coupled to thehigh-frequency heating furnace (13 a) at its exit side, through whichthe heat transfer tube (B) coming out from the high-frequency heatingfurnace (13 a) can pass in the length direction thereof. The heattransfer tube (B) is supplied in the length direction so as to passthrough the high-frequency heating furnace (13 a) and cooling furnace(13 b) in order, so that every portions of the heat transfer tube (B) isheated in the high-frequency heating furnace (13 a) and then cooled inthe cooling furnace (13 b), one by one and continuously, respectively.

[0058] The coiling in-line mechanism (14) includes a rotational axis towhich the body (C1) of the bobbin (C) is attached detachably, and acoiling machine (14 a) rotating the body (C1) attached to the rotationalaxis in the coiling direction of the heat transfer tube (B) on the body(C1). That is, in this embodiment, the heat transfer tube (B) is coiledin line directly on the bobbin for carrying out (C).

[0059] A process of manufacturing the heat transfer tube by themanufacturing device comprising the groove working mechanism (11), theforming mechanism (12), the annealing mechanism (13) and the coilingin-line mechanism (14) will be described referring to FIG. 1.

[0060] Basically, the process consists of groove working step (1) by thegroove working mechanism (11), forming step (2) by the forming mechanism(12), annealing step (3) by the annealing mechanism (13) and coilingin-line step (4) by the coiling in-line mechanism (14).

[0061] Specifically, in the groove working step (1), the copper platecarried in is removed from the bobbin by the un-coiler, and the embossroll is pressed against one of the surfaces of the copper plate to workgrooves. By this groove working, the soft copper plate is hardened fromHV(0.5) 60-68 to HV(0.5) 100-130, and its elongation percentagedecreases from more than 40% to less than 35%.

[0062] Then, in the forming step (2), the copper plate is formed in atube shape gradually by pressing it against a roll mold, with grooveslocated on its inside surface, and its attached joint portions arewelded together, and then it is narrowed down to a certain diameter.Here, in this embodiment, the heat transfer tube (B) formed in theforming step (2) is once coiled roughly with an appropriate diameter ina basket.

[0063] Next, in the annealing step (3), the heat transfer tube (B) inthe basket is supplied in the length direction at a certain speed (forexample approximately 10-200 m/minute), and every portions of that isheated at a certain temperature (for example 700° C.) in thehigh-frequency heating furnace (13 a) and then cooled down by a water toa certain temperature (for example 30-40° C.) in the cooling furnace (13b), one by one and continuously, respectively. Accordingly, the heattransfer tube (B) that has been hardened is softened and comes back tothe original state with its elongation percentage of more than 40%.Here, in this embodiment, a length of heating area where the heattransfer tube (B) is heated passing through the high-frequency heatingfurnace (13 a) is set to approximately 1 m, and every portions of theheat transfer tube (B) in the length direction are heated at a certaintemperature for a period of, for example 0.1-0.2 seconds.

[0064] In the coiling in-line step (4), as shown in FIG. 3(a), the heattransfer tube (B) annealed in the annealing step (3) is coiled directlyon the body (C1). Accordingly, as shown in FIG. 3(b), the heat transfertube (B) that is coiled in line on the body (C1) can be provided. Next,as shown in FIG. 3(c), a pair of flanges (C2, C2) are attached to theboth ends of the body (C1) on which the heat transfer tube (B) is coiledin line, and accordingly the heat transfer tube (B) that is coiled inline on the bobbin for carrying out (C) can be provided. Here, in thecoiling in-line step (4), one flange (C2) may be attached to one end ofthe body (C1) at need.

[0065] Therefore, according to this embodiment, grooves are formed onthe soft copper plate by rolling with hardening, and the copper plate isformed in a tube shape, and then the heat transfer tube (B) with itsinside surface having groove is coiled in line. On the other hand, whenthe hardened heat transfer tube (B) is annealed and softened, the tube(B) is coiled in line after being annealed, contrary to the conventionalway in which the tube is annealed and softened after being coiled inline. Therefore, a situation can be avoided where contacted portions ofthe heat transfer tube (B) stick together by annealing and accordinglyit may not be easy for the coiled tube to be removed.

[0066] Further, the annealed heat transfer tube (B) is coiled in line onthe body (C1) of the bobbin for carrying out (C). Therefore, works ofinstalling the heat transfer tube (B) to the bobbin for carrying out (C)can be simplified so as to be just a work of installing the flange (C2)to the body (C1).

[0067] Here, in this embodiment, the heat transfer tube (B) with itsinside surface having a groove for a heat exchanger is manufactured byusing a soft metal plate made of copper alloy is described. However, thepresent invention is not limited to this particular material, and anyother materials may be adopted.

INDUSTRIAL APPLICABILITY

[0068] As described above, the method and the device for manufacturing asoft metal tube of the present invention are useful in manufacturing asoft metal tube which working with hardening is applied to and arecoiled in line on, especially in manufacturing a soft metal tube withits inside surface having a groove for a heat exchanger.

1. A method for manufacturing a soft metal tube, comprising: workingstep (1) of working a soft metal plate with hardening of the soft metalplate; forming step (2) of forming the metal plate worked in saidworking step (1) into a metal tube (B); annealing step (3) of annealingand softening the metal tube (B) that is hardened in said working step(1) and formed in said forming step (2); and coiling in-line step (4) ofcoiling the metal tube (B) softened in said annealing step (3) in line.2. The method for manufacturing a soft metal tube of claim 1, whereinsaid working step (1) comprises rolling to harden the metal plate. 3.The method for manufacturing a soft metal tube of claim 1, wherein: saidannealing step (3) comprises step of annealing every portions of themetal tube (B) one by one and continuously while the metal tube (B) issupplied in the length direction; and said coiling in-line step (4)comprises step of coiling the metal tube (B) in line successively whilethe metal tube (B) is carried out form said annealing step (3).
 4. Themethod for manufacturing a soft metal tube of claim 1, wherein saidmetal tube (B) is carried out in a state where it is coiled in line on abobbin for carrying out (C), and the metal tube (B) is coiled in line onthe bobbin for carrying out (C) in said coiling in-line step (4).
 5. Themethod for manufacturing a soft metal tube of claim 4, wherein saidbobbin for carrying out (C) comprises a body (C1) on which the metaltube (B) is coiled and a flange (C2) which is attached to at least oneend of the body (C1), and the metal tube (B) is coiled in line on thebody (C1) and the flange (C2) is attached to the body (C1) with themetal tube (B) coiled in line in said coiling in-line step (4).
 6. Themethod for manufacturing a soft metal tube of any of claims 1-5, whereinsaid metal tube (B) is a heat transfer tube with its inside surfacehaving plural lines of grooves for a heat exchanger and said metal plateis a copper plate, said woring step (1) comprises step of forming plurallines of grooves on one surface of the copper plate by rolling, and saidforming step (2) comprises step of forming the copper plate into theheat transfer tube (B) for the heat exchanger in such a manner that thegrooves are located on an inside surface of the tube.
 7. A device formanufacturing a soft metal tube, comprising: working means (11) forworking a soft metal plate with hardening of the soft metal plate;forming means (12) for forming the metal plate worked in said workingmeans (11) into a metal tube (B); annealing means (13) for annealing andsoftening the metal tube (B) that is hardened in said working means (11)and formed in said forming means (12); and coiling in-line means (14)for coiling the metal tube (B) softened in said annealing means (13) inline.
 8. The device for manufacturing a soft metal tube of claim 7,wherein said working means (11) rolls the metal plate accompanyinghardening of the metal plate.
 9. The device for manufacturing a softmetal tube of claim 7, wherein: said annealing means (13) comprisesmeans for annealing every portions of the metal tube (B) one by one andcontinuously while the metal tube (B) is supplied in the lengthdirection; and said coiling in-line means (14) comprises means forcoiling the metal tube (B) in line successively while the metal tube (B)is carried out from said annealing means (13).
 10. The device formanufacturing a soft metal tube of claim 9, wherein said annealing means(13) comprises a heating furnace (13 a), through which the metal tube(B) can pass in the length direction, and a cooling furnace (13 b)coupled to the heating furnace (13 a) at its exit side, through whichthe metal tube (B) coming out from the heating furnace (13 a) can passin the length direction, and every portions of the metal tube (B) in thelength direction passing through are heated in the heating furnace (13a) and then cooled in the cooling furnace (13 b), one by one andcontinuously, respectively.
 11. The device for manufacturing a softmetal tube of claim 7, wherein said metal tube (B) is carried out in astate where it is coiled in line on a bobbin for carrying out (C), andsaid coiling in-line means (14) coils the metal tube (B) in line on thebobbin for carrying out (C).
 12. The device for manufacturing a softmetal tube of any of claims 7-11, wherein said metal tube (B) is a heattransfer tube with its inside surface having plural lines of grooves fora heat exchanger and said metal plate is a copper plate, said workingmeans (11) forms plural lines of grooves on one surface of the copperplate by rolling, and said forming means (12) forms the copper plateinto the heat transfer tube (B) for the heat exchanger in such a mannerthat the grooves are located on an inside surface of the tube.